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arXiv · astro-ph/0209325

Detection of Solar-like Oscillations in the G7 Giant Star xi Hya

S. Frandsen·F. Carrier·C. Aerts·D. Stello·T. Maas·M. Burnet. H. Bruntt·T. C. Teixeira·J. R. de Medeiros·F. Bouchy·H. Kjeldsen·F. Pijpers·J. Christensen-Dalsgaard
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Abstract

We report the firm discovery of solar-like oscillations in a giant star. We monitored the star xi Hya (G7III) continuously during one month with the CORALIE spectrograph attached to the 1.2m Swiss Euler telescope. The 433 high-precision radial-velocity measurements clearly reveal multiple oscillation frequencies in the range 50 - 130 uHz, corresponding to periods between 2.0 and 5.5 hours. The amplitudes of the strongest modes are slightly smaller than 2 m/s. Current model calculations are compatible with the detected modes.

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S. Frandsen, F. Carrier, C. Aerts, D. Stello, T. Maas, M. Burnet. H. Bruntt, T. C. Teixeira, J. R. de Medeiros, F. Bouchy, H. Kjeldsen, F. Pijpers, J. Christensen-Dalsgaard. 2002-09-17. Detection of Solar-like Oscillations in the G7 Giant Star xi Hya. https://doi.org/10.1051/0004-6361%3A20021281

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